BONN, Germany (Landscape News) — An estimated 340 million hectares of woody vegetation are degraded across Africa’s fragile dry areas – the result of rising populations, shifting land use patterns, and the adverse impacts of climate change.
This loss threatens the viability of rural livelihoods and ecosystems, topics delegates are preparing to discuss in the lead up to a Global Landscape Forum in Nairobi this month. Without roots to bind soils deforested lands are vulnerable to erosion and impaired soil health; clearing trees damages the structure and diversity of plant communities – bringing more disease and invasive species; habitats become fragmented – posing threats to biodiversity; and deforestation undermines the carbon sequestration potential of forests.
RESTORING DEGRADED FORESTS
Saving the continent’s dwindling forests will depend on effective and strategic restoration efforts – to improve soil functions, enhance the availability of water, and increase woody biomass to elevate levels of soil carbon. Where possible remaining trees and forest fragments should be conserved to allow natural regeneration, acting as both sources and receivers of tree genetic material in the form of pollen and propagules.
Establishing “exclosures” – land that has been set aside to prevent or reduce degradation from livestock grazing – have proven to be an effective restoration measure. A study by the World Agroforestry Centre (ICRAF) in northern Ethiopia, for instance, demonstrated that soils in exclosure lands were healthier than those in communal grazing areas and contained significantly higher levels of nitrogen, phosphorous, and carbon exchange capacity.
The sustainable land management practices that target rehabilitation efforts within exclosures include coppicing, involving the periodic cutting back of vegetation to ground level so that growth can be stimulated. The practice produces resilient vegetative shoots that demonstrate resistance to fire and other forms of disturbance. Coppiced trees are also faster growing and less susceptible to drought than seedlings because they are supported by below-ground biomass and larger root systems.
PARTICIPATORY MANAGEMENT STRATEGIES
Another promising strategy is “functional ecology.” This practice links land use with the traits and ecosystem functions of specific tree species, and rests on the premise that different types of vegetation influence soil properties, soil health, and functions in divergent ways. In essence, it means that specific types of vegetation can be used to rehabilitate land in targeted ways – to support a particular land use, for example, or to overcome a specific challenge or deficiency in the soil.
Decisions to support functional ecology approaches are supported by the Agroforestry Species Switchboard, which provides information on trees and tree-based development activities. Technical experts are another source of information.
Equally, so are local communities who know their environments intimately. “Choosing species for a given purpose or function could be helped by the participation of local people,” says Ermias Betemarriam, a researcher at ICRAF studying land degradation and rehabilitation. “By including them in restoration efforts we can benefit from their local knowledge which is invaluable.”
“Bottom-up” management regimes have been effective in other management regimes, including preventative measures that help local communities generate income from the sustainable utilization of forest resources. Involving local communities in planning, management and evaluation activities has also encouraged a sense of ownership and ensures community needs are adequately met.
Incentives are key. According to Keith Shepherd, a Principal Soil Scientist at ICRAF: “We can encourage farmers to invest in sustainable land management by providing incentive mechanisms, whether they be subsidies, rewards or linking the management of natural resources to income-generating activities.”
There are signs that African governments recognize the threats posed by degradation. Governments in dryland regions are already committed to restoration efforts and contribute to several important regional and global initiatives such as the Bonn Challenge and African Forest Landscape Restoration.
Some are also pursuing land degradation neutrality (LDN) targets, supported by international organizations such as the U.N. Convention to Combat Desertification (UNCCD). A conceptual framework explains LDN processes and principles and offers recommendations to guide implementation, including protecting the rights of land users, integrating planning and implementation into existing land use planning processes, and balancing economic, social, and environmental sustainability.
African governments are also being encouraged to rapidly adopt proven technologies and climate-resilient farming methods as these will have important implications for the survival of the continent’s forests. After all, by sustainably intensifying agricultural production on existing land we can meet the additional food demands of a growing population while avoiding the need to clear more trees and forests.
Learn more about this topic. Check out the agenda for the upcoming Global Landscapes Forum in Nairobi, Aug. 29-30 here.